Prosthesis

The Alpha Leg is complete

admin — Thu, 25 Aug 2011 01:06:22 +0000

In a blinding push from the team, especially Mark, Ryan and Dylan the Alpha Leg was completed at the 11th hour for deployment at the Burning Man festival in Nevada, USA. This was where the Mondo Spider was unveiled in 2006 and this year will be where Lab-mate and Mondo Spider co-creator Charlie Brinson’s Titanoboa will first slither in all it’s glory. The Leg is truly imposing, and a sight to behold in the gleaming reality of hard steel, especially after staring at the flawless rendered image of it on the computer screen for so long. This machine has a serious presence. And although Prosthesis is still untested and the hydraulic system is limited to only 300psi because of a pump problem, it is still a worthy and proud milestone to have her standing in one piece and to bring her to where she will one day run free – the endless salt flats of the Black Rock Dessert!

See a video of the leg in action here.

The base shows is size

Jonathan — Tue, 01 Mar 2011 08:33:12 +0000

We’ve been plugging way at putting the base together and it is finally taking shape. At this point, the scale of this project begins to sink in. We need to use the crane to flip the huge structure so we can start TIG welding in the finer structure underneath to give it strength and stiffness. Time to teach the team to TIG weld.

Alpha leg design on the critical path

Jonathan — Mon, 28 Feb 2011 07:43:32 +0000

With the base well under way and the UBC Engineering Suspension and Hydraulics teams blazing ahead with their designs the pressure is on to have a leg design ready for fabrication. Finding the balance between an elegant and sexy leg, and something that can be built in time by the ever more skillful team becomes critical. This image shows a well well evolved Upper Leg and a very simplified Lower link (the square tubes). Square tubes are not sexy, but they’re easy to fabricate with.

Power comes in cylindrical form

Jonathan — Sun, 27 Feb 2011 01:06:56 +0000

It may seem odd that I’m so excited by shiny, red, 2” x 8” hydraulic cylinder, but this is the stuff of childhood dreams for me. This 15kg of steel and thick red paint can deliver 19kW (25hp+) of power and 4200kg (9400lb) of force to an area the size of your thumb. That’s a lot of push. According to our calculations, that’s enough push to make 600kg of steel jump – given the right engineering and sufficient pilot training (!). The four guys flanking me, (Scott : Max : [me] : Matt : Dan) are from the team of five UBC Engineering students I’ve sponsored to help design the hydraulics (Dan E. not shown). They spec’d this cylinder to power the knee of Prosthesis Phase-Alpha and it will be controlled by the sophisticated regenerative hydraulic valving system they developed. It will be integrated with the positional feedback exo-frame interface and put to the test on the tower. The students are hot on the our tail now and it’s my job now to surround this shiny, red cylinder with a steel leg robust enough to deliver all that power to the ground with style.

One step ahead

Jonathan — Sat, 26 Feb 2011 08:04:42 +0000

The design is progressing nicely. There is so much engineering and design that goes into producing fabrication ready parts, but it’s not until all the prep work is done that you can finally generate drawings and start cutting metal. It’s like painting a room. Clean the walls, cover the funiature, fill the holes and then, in one busy weekend, the room suddenly changes colour. This CAD rendering represents only what’s ready for painting.

At the helm

Jonathan — Sat, 26 Feb 2011 06:55:40 +0000

This is my usual position during our intensive build sessions in the eatART Lab. I have a team of dedicated and hungry fabricators that I need to feed parts to. The tight timeline we’re gunning for in order to get the prototype leg built in time for the hard working UBC students means that design and fabrication must take place in parallel. This is a deviation from the ideal of having everything fully designed before the build begins, but with enough focus, and the proper systems in place, parts can be fed out Just-In-Time. Crank.

Like moths to a flame

Jonathan — Sat, 26 Feb 2011 06:05:39 +0000

As the team all learn the basics of wire feed welding the pace picks up.
Left:An attentive group watches how it’s done. Right: Polly takes the torch and lays some beads.

Dylan and Mark try their hands at flux-core

Jonathan — Thu, 24 Feb 2011 05:44:14 +0000

On John’s advice (insistence) we used flux-core wire feed to weld the sizeble members that make up the base of Prosthesis. Dylan is breaking in his “Project Hoodie”. It’s cleanliness will be used as a metric for his shop time as the project progresses.
The flux in flux-core, as John explains, consumes the oxygen and other impurities on the metal’s surface as it vaporizes, allowing lots of metal joining heat to be poured in to the weld and minimal cleaning of the salvaged metal.

John shares his skills on the first pieces of metal

Jonathan — Thu, 24 Feb 2011 05:04:03 +0000

Veteran ship builder John Blake lends his decades of experience building large things to the team. With the extent of my intuition topping out at 1″ tubing, this sort of knowledge is just what we need to make sure the huge 4″ x 4″ x 1/4″ tubing for the base goes together properly. Mark and Dylan soak it in.

School is in – the Prosthesis team has class

Jonathan — Thu, 17 Feb 2011 23:51:36 +0000

As a way to entice volunteers to help me build Prosthesis, I have offered to teach a select group of friends who have expressed interest in helping build Prosthesis over the years, what I know about welding and fabrication. I learned most of what I know from my experience building the Mondo Spider. I’ve taken a six week course at BCIT (a local trade school) but once you know the fundamentals, the only thing that can really teach you to TIG weld is practice.

The original plan was to train everyone on the CNC tubing cutter and have them build a project of their own design, like a bike rack, or a coffee table, but with Project Alpha on the critical path, it’s in to the deep end and sink or swim. Luckily, I’m not the only one with some experience on the team. Veteran ship builder, John Blake will be lending his decades of experience and my right-hand man on the Spider legs, Ryan Johnston will be helping people get the feel for the torch. Mark Eijsermans also has foothold on metal fab from his work on the Gramorail and Tim Lukian has been producing some fine brazed CrMo bike racks of late. Polly Tan and Brad Sieber have carpenters hands and the rest of the team all bring focus and dedication to the table. I have a feeling I have a ringer team on hand.